On the plane

Only minutes before the catastrophe, flight was still normal. Oceanic 815 was at cruise altitude, straight-and-level, within a clear air mass. There was no turbulence. Jack looked out on the left wing, and exchanged small talk with the flight attendant, Cindy and passenger Rose Nadler. ("Pilot, Part 1")

Turbulence began

On the island

As Desmond rushed back into the Swan, a pre-recorded system failure warning message was repeated, while the entire station was shaking, and dust was falling from the ceiling outside the concrete wall, suggesting that the Swan was under intense structural stress. ("Live Together, Die Alone, Part 1")

Violent turbulence

On the island

Inside the Swan station, Desmond anxiously tried to enter the Numbers. Metal objects such as cans began to fly through the air toward the concrete wall, demonstrating that the magnetic field behind it was growing much stronger than normal. ("Live Together, Die Alone, Part 1")

At the Barracks, the shaking was so violent that dishes fell off of shelves, but there was no evidence of metal behaving abnormally. ("A Tale of Two Cities")

At the Barracks, the earthquake stopped. Juliet and her guests went outside. More of the Others, including Ben, Ethan and Goodwin also gathered on the lawn in front of the houses. Looking towards the sky, they could suddenly hear the sound of a plane. Moments later, Oceanic Flight 815 descended into their view. ("A Tale of Two Cities")

On the plane

The aircraft began a rapid descent. Breathing masks deployed in most sections of the aircraft, although they, for some reason, failed to deploy in at least one part of the Tail Section. The passengers' heads were pulled back against the headrests. The view through Kate's window indicated that the aircraft was nose-down about 15 degrees. The aircraft was shaking. The engines were whining, the noise increasing in volume and pitch. Metallic groaning continued. ("Pilot, Part 1") ("Pilot, Part 2")

Partial recovery

As Oceanic Flight 815 came within sight of the Others, it appeared to have made a partial recovery. Flight appeared relatively straight-and-level. The aircraft was descending, right wing slightly low, roughly between 2,000ft and 5,000ft in altitude. It was trailing a cloud of black smoke from the right engine. Turbofan engine noise, as heard from the perspective of the Others, seemed basically normal.

However, a black band was already visible at the incipient point of separation of the tail section as the plane came into view. ("A Tale of Two Cities")

Break-up began

Even though the magnetic force pulling the plane down had stopped, Oceanic 815 began to lose its structural integrity. A large, white rectangular object, roughly the size and shape of the forward cargo door, but perhaps larger, separated from the right side of the aircraft. Black smoke continued to trail from the right engine.

As the object appeared to reach the height of the tail, a second very narrow black band appeared at the future point of separation of the nose section.("A Tale of Two Cities")

Tail section separated; Explosion of right engine

As the plane continued to shake, the tail section separated from the rest of the plane, and passengers not wearing their seatbelts were instantly sucked out of the cabin. ("Pilot, Part 2") At the instant the tail section had completely separated from the plane, the right engine exploded and separated from the wing. From the Barracks' point of view, a loud boom could be heard.

The front landing gear separated from the front of the plane and began falling. ("A Tale of Two Cities")

General disintegration

Most of the left wing past the engine separated. Other pieces separated, including a large, black rectangular piece and two wheeled pieces of the landing gear. The right engine, trailing flames and black smoke, continued to fall. ("A Tale of Two Cities")

In the mid-section, after the tail section separated, an emergency-beeping noise and engine noise continued, suggesting that the nose/mid-section was still partially operational. ("Pilot, Part 2")

Nose and mid-section continued

The nose section, the mid-section, the stub of the left wing, the left engine, and part of the right wing remained together. This part of the aircraft, which contained most of the future survivors of the crash, appeared to retain some lift and it continued partially forward in the direction of the flight path. The tail section, which apparently caught the air stream and slowed down due to drag, began a more precipitous fall. As it fell, it assumed an aft-downward attitude, possibly because that was its most aerodynamic attitude.

As they continued their separate trajectories, the tail seemed to be falling toward the right and the front section toward the left of the flight path. The effect was one of "blossoming outward" from the point of separation. ("A Tale of Two Cities")

Sections crashed

The tail section crashed in the ocean not too far from the beach, tumbling down from the direction of the sea toward the beach. Immediately prior to impact, its attitude was "nose-up," in a sledding position that may have maximized the chances of survival for the Tailies. Moments after the impact of the tail section, other pieces of debris all began to hit on or around the beach on the tailies' side of The Island. ("The Other 48 Days")

The cockpit section crashed into the jungle, short of the beach where the mid-section crashed. ("Pilot, Part 1")

The cargo compartment crashed inside a cave, also not too far from beach where the mid-section crashed. ("White Rabbit")

The mid-section crashed on a beach on the opposite side of the island from where the tail section had crashed. Although the starboard engine separated from the fuselage while still in view of the Barracks, its trajectory remained miraculously identical to that of the fuselage, to the point that it landed on the same beach less than 10 meters away from the intact fuselage. ("Pilot, Part 1"). According to Sayid, the fuselage first cartwheeled through the jungle before coming to its resting place. ("The Moth")

(Note: The actual crashes of the cockpit section, the cargo compartment and the mid-section have never been shown on the show.)

Contrails followed the fragments part of the way down to ground level. A trail of black smoke followed a flaming fragment all the way to ground level. Columns of dark smoke rose from two crash sites.

The "blossoming outward" effect was more evident. The trails to the right, presumably the tail section and other pieces, landed either on or near a beach. Other pieces fell either over the Island or on its far side to the left.

Alternate depictions in Via Domus

In the opening sequence of Via Domus, Elliott is a passenger on the plane and witnesses the turbulences, the tail section of the plane breaking off, and eventually also the cockpit section breaking off, with people being sucked out of the plane on both ends. ("Force Majeure")

In the ending sequence of "Worth A Thousand Words", Elliott is on sailboat leaving the Island, but somehow ends up witnessing the mid-air break-up of Flight 815 again, this time from below. In this version, the breakup seems to be occurring a lot faster than at the beginning of "A Tale of Two Cities".